If your clild is leaving from school for a school trip, you should record their travel palns from the time that they return from that trip and leave the care of the school. This may well be the onward journey directly from the airport, or from school if they are returning to the school before going home. You should “Any Date Not Shown Above” and associate the day they are returning from the trip with the start of the holiday.
We have recorded an example below to show you how you can make this work.